The present invention relates to methods for self-applying appearance enhancing protective coatings over the inner surfaces of truck beds, and related applications in other fields of endeavor. In particular, the present invention relates to a process for applying a permanent protective polyurethane elastomeric coating, which protective coating is capable of being mixed and then brushed or troweled by a user over the interior walls of a truck bed without any prior expertise, background or training.
Conventional systems for applying protective elastomeric coatings to the inner surfaces of truck beds have been plagued by several longstanding problems. Likewise, there is lacking in the art a suitable `do-it-yourself` means to apply protective urethane coatings. Prominent among truck users is a particular need to protect the inner painted surfaces of the bed walls that are commonly associated with various types of pickup trucks. For example, any exposed inner wall surface of a truck bed which is painted is prone to scratches, peeling and the like damage by contact with things being transported. Rust is often a direct result of violation of the integrity of such inner wall paint surfaces in combination with the natural forces of weather. Once corrosion gains a foothold, degradation of the entire truck bed soon follows.
Further, conventional truck "bed liner" coating systems traditionally require installation by an expert, or are prohibitively expensive or otherwise cumbersome. The only known type of do-it-yourself product is made up of a pre-formed bed liner which is designed to be dropped into the bed of a truck in a pre-assembled state. This known liner is prohibitively expensive, in addition to requiring installation assistance from at least several persons.
Likewise, attempts at using different lining materials have not adequately addressed the longstanding needs ameliorated by the instant teachings. For example, wooden truck bed liners are subject to damage and have durational life spans requiring that they be replaced at least several times during the lifetime of the average truck.
Conventional chemical treatments utilizing urethane and epoxy materials and mixtures are likewise known as available for use protecting various substrates. However, as applied to the problem solved by the present invention, attempts within the prior art have heretodate been subject to the same constraints enumerated above, namely, they are ineffectual generally in that they require frequent replacements and experts for installation. The teachings of the present invention have ameliorated this longstanding problem, and as explained below--offer an uncomplicated chemical solution which substantially improves over the prior art. An explanation of technical rudiments of same is provided hereafter.
By way of background, attention is called to the following United States Letters Patents which have each been examined during the course of the present invention and found to be technically distinguishable from the instant teachings, as claimed subject matter created by the present inventor which is respectfully submitted to be new, novel and unobvious within the definition prescribed by statute:
U.S. Pat. Nos. 5,436,302; 5,317,076; 5,221,707; 5,216,093; 5,096,992; 4,933,416; 4,636,546; 4,661,532; 4,511,626; 4,087,296; and 3,894,165.
The majority of these prior art references are readily distinguishable in that they merely define the state of the art in urethane technology, namely each showing that it is know n to combine the MDI (diphenylmethane diisocyanates or isocyanate-functional derivatives) chemical family with polyols to produce elastomeric compositions. This is done by introducing MDI to a hydroxyl group and forming a urethane molecule. Such specific applications have grown out of the original disclosures relating to the initial development of urethane from the 1940's in Germany.
Conventional use of urethane for substrate protection is disclosed by the prior art which was examined, and found to be readily distinguishable from the instant teachings. This is shown, for example, by U.S. Pat. No. 4,087,296 issued to Thomas Hooker disclosing a method for applying membrane-covered rigid foam to building surfaces, such as a roof.
U.S. Pat. No. 4,636,546 issued to Yen-Yau H. Chao disclosing a process for preparing modified polymer emulsion adhesives useful, for example, in bonding expanded vinyl. Likewise, U.S. Pat. No. 4,933,416 which issued to Herbert R. Gillis, et al. disclosed general apsects of the properties and usages of polyisocyanate compositions.
U.S. Pat. Nos. 5,221,707; 5,317,076; 4,511,626; and 5,436,302 each relate to general aspects of elastomeric compositions with DMI and combination of same with fillers. It is noted that nothing among these disclosures either suggests the solution proffered by the instant teachings, or the particular fillers used by the present invention to achieve its novel objectives.
Finally, U.S. Pat. No. 5,216,093 issued to Shuichi Hayashi revealed a low-temperature curing epoxy resin composition, which demonstrates only that compounds such as the present invention are known to be curable at ambient temperature and pressure.
However, U.S. Pat. No. 4,661,532 ("the '532 patent") which issued to Morin on Apr. 28, 1987 and disclosed a COAL TAR CONTAINING FOAMING URETHANE COMPOSITION AND A METHOD FOR REPAIRING DEFECTS IN STRUCTURAL COMPONENTS, enumerates an additional problem solved by the teachings of the present invention. In specific, the '532 patent demonstrates that the "recycle of used structural components" (Col. 1, line 22) is appropriate for combination with a plurality of different chemical materials, including urethanes. However, the '532 patent limits itself to the generation of `two package urethane compositions` and a method using same to repair structural members having surface defects. Likewise, its nature as a foaming urethane composition differentiates it from the instant teachings.
In essence, the teachings of the present invention have wedded the solution to these two technically distinct problems in generating both a process for coating the bed liner of a truck and an economically efficient means for utilizing a recycled tire by-product. A brief technical synopsis sets forth a rudimentary background for the underlying mechanism for the novel teachings offered herein for consideration.
A plastic is defined as any organic material with the ability to flow into a desired shape when heat and pressure are applied, and to retain the shape when they are withdrawn. A plastic is made up principally of a binder, together with plasticizers, fillers, pigments, and other additives. The binder gives a plastic its main characteristics and usually its name. Thus, for example, polyvinyl chloride is both the name of a binder and the name of a plastic into which it is made. Binders may be natural materials, e.g. cellulose derivatives, casein or milk protein. But more commonly binders are synthetic resins. In either case, the binder materials consist of very long chainlike molecules called polymers. Cellulose derivatives are made from cellulose, a naturally occurring polymer; casein is also a naturally occurring polymer.
Plasticizers are added to a binder to increase flexibility and toughness. Fillers, such as carbon black, are added to improve particular properties, e.g. hardness or resistance to shock. Pigments are used to impart various colors. Plethoric combinations of both pigments and fillers are known to those skilled in the art, and it is possible to impart a multiplicity of desired finishes or affects utilizing same. Likewise, many combinations of the properties of hardness, durability, elasticity, and resistance to heat, cold and acid, can be obtained in a plastic by way of manipulation of requisite parameters.
Generally, there are two type of plastics: thermosets, which cannot be resoftened after being subjected to heat and pressure; and thermoplasts, which can be repeatedly softened and remolded by heat and pressure. Plastics, also called synthetic resins are polymerized, or built up, from small simple molecules called monomers. When beat and pressure are applied to a thermoplastic binder, these chainlike molecules slide past each other giving the material "plasticity". By contrast, when heat and pressure are initially applied to a thermosetting binder, the molecular chains become joined or "crosslinked", thus preventing any slippage if heat and pressure are reapplied.
Thermosets are usually supplied as partially polymerized or as monomer-polymer mixtures. Cross linking is achieved during fabrication using chemicals, heat or radiation; this process is called curing or vulcanization. Important thermosets include phenol-formaldehyde, epoxy, diallyl phthalate, polyester, urea-formaldehyde, and melamine-formaldehyde, among others.
Plastic articles are commonly manufactured from thermoset plastics in which desired shapes are fashioned by molding. The monomer or partially polymerized mixture is treated with a curing agent and may be placed in a mold to harden. Reinforcement means can be introduced during this process, which is used for designs with intricate shapes and great variations in wall thickness. Among the plastics used for making plastic articles are epoxy resins, polypropylene, polyolefins, polyethylene, vinyl plastics, polycarbonates, polyacrylics, polyvinyl chloride polystyrene, phenolics, ureas, melamines, polyesters, silicones, rubbers, and polyurethanes. Likewise, rubbers as polymers of isoprene are effective for creating application specific uses and resultant product with desired inherent properties.
Plastics, including rubbers admixed with same, may be used as such, or may be reinforced by other reinforcing materials . Similarly, a wide variety of materials are made by combining fiberglass with plastics. These materials, which are rust proof, are molded into the shape required or pressed into flat sheets, as discussed within the context of the truck-bed liners requiring expert installation.
According to the instant teachings, the painted surface of a truck, or deck, or other application is protected from rust or other damage. This polyurethane elastomeric coating incorporates ground rubber pellets, enabling it to overcome the principal drawbacks of the prior art, and making it trowelable, brushable or easily applied generally by a single user. Both of these distinct, but significant concerns is ameliorated by the present invention as developed below and defined by the claims below. Likewise, it is noted that the composition of the present invention is readily differentiable from the only other do-it-yourself means for coating a substrate which is applied by a spray nozzle on a bottle. As discussed hereinafter, the teachings of the present invention require that a consistency be imparted to the compound through the addition of ground rubber--which precludes such spray nozzle applications.
It is respectfully submitted that any U.S. Letters Patent references offered herein for consideration, but not distinguished in detail, merely define the state of the art or show the type of systems which have been used to alternately address those issues ameliorated by the teachings of the present invention. Accordingly, further discussions of these references has been omitted at this time due to the fact that they are readily distinguishable from the instant teachings to one of skill in the art.